This disambiguation page lists articles associated with the title UPD. If an internal link led you here, you may wish to change the link to point directly to the intended article.
Chronic smokers often have difficulty breathing because they develop Chronic Obstructive Pulmonary Disorder, or COPD. The two diseases that fall under that category are emphys â¦ ema and chronic bronchitis.
COPD, or chronic obstructive pulmonary disease, is a type of lung disease that makes it difficult to breathe. The condition is typically caused by long-term exposure to lung irritants, such as cigarette smoke or air pollution. People with COPD usually experience shortness of breath, wheezing, and coughing. If you have COPD and enjoy traveling, then you probably already know that high altitude can make COPD symptoms worse.